Police are investigating how a report into the death of Amy Winehouse came to be sent to the wrong address.

The report – believed to contain material relating to the inquest into how the singer died – should have been dispatched to Winehouse's family, but was instead handed in at a London police station last week.

A spokesman for the Metropolitan police said: "Police were informed on Friday 21 October that material relating to a forthcoming inquest may have been delivered to an incorrect address. On Friday evening, material was handed in at a north London police station. Inquiries are now under way to establish the full circumstances of this matter."

The singer, who was 27, was found dead in her home in north London on 23 July. The inquest into her death was opened and adjourned on 25 July and is due to reopen on Wednesday.

"Results indicate that alcohol was present, but it cannot be determined as yet if it played a role in her death," a family statement said.

"The family would like to thank the police and coroner for their continuing thorough investigations and for keeping them informed throughout the process. They await the outcome of the inquest in October."

The foundation, launched in September, aims to support "charitable activities in both the UK and abroad that provide help, support or care for young people, especially those who are in need by reason of ill health, disability, financial disadvantage or addiction".